There has been known an internal combustion engine which has a supercharger, a bypass passage bypassing a turbine of the supercharger, and a wastegate valve (hereinafter, sometimes also referred to as a “WGV”) arranged in the bypass passage. Then, there has also been known a technique of raising the temperature of an exhaust gas purification catalyst arranged at the downstream side of a merge portion between a bypass passage and an exhaust passage by using an exhaust gas of relatively high temperature having passed through the bypass passage, at the time of cold start of an internal combustion engine.
In patent literature 1, there is disclosed a technique in which at the time of cold start of an internal combustion engine, the degree of opening of a WGV is controlled so that an exhaust gas flowing out from a bypass passage into an exhaust passage (hereinafter, sometimes also referred to as a “bypass exhaust gas”) impinges directly against an exhaust gas purification catalyst, whereas in a supercharging operation region, the degree of opening of the WGV is controlled so that the bypass exhaust gas does not impinge directly against the exhaust gas purification catalyst.
In addition, in patent literature 2, there is disclosed an exhaust gas purification apparatus in which louver members are arranged before and after the exhaust gas purification catalyst. In the exhaust gas purification apparatus, each of the louver members has a slit and a ramp, and it is constructed such that the direction of flow of an exhaust gas having passed through the slit can be changed by the ramp.